Next Row (RS): Cast on 46 (46, 44, 42, 40) sts, k to end of row - 172 (182, 190, 198, 206) sts at the end of this row.Next Row: Cast on 46 (46, 44, 42, 40) sts, p to end of row - 218 (228, 234, 240, 246) sts at the end of this row.

What I'm not sure about is what cast-on method would work best at the BEGINNING of a row.....